The article provides a comprehensive overview of osteoarthritis (OA), emphasizing its multifactorial nature and the involvement of various joint tissues. OA, often referred to as degenerative joint disease, is characterized by abnormal remodeling of joint tissues driven by inflammatory mediators. Key risk factors include age, gender, prior joint injury, obesity, genetic predisposition, and mechanical factors. The pathological changes in OA joints include degradation of articular cartilage, thickening of subchondral bone, osteophyte formation, synovial inflammation, degeneration of ligaments and menisci, and hypertrophy of the joint capsule. The article discusses the specific changes in each joint tissue, such as the activation of chondrocytes, matrix degradation, and the role of inflammatory mediators. It also highlights the importance of biomechanical stress, aging, and the interaction between different tissues in the progression of OA. The authors emphasize the need for a systems approach to understand the complex interactions within the joint and to develop effective treatments.The article provides a comprehensive overview of osteoarthritis (OA), emphasizing its multifactorial nature and the involvement of various joint tissues. OA, often referred to as degenerative joint disease, is characterized by abnormal remodeling of joint tissues driven by inflammatory mediators. Key risk factors include age, gender, prior joint injury, obesity, genetic predisposition, and mechanical factors. The pathological changes in OA joints include degradation of articular cartilage, thickening of subchondral bone, osteophyte formation, synovial inflammation, degeneration of ligaments and menisci, and hypertrophy of the joint capsule. The article discusses the specific changes in each joint tissue, such as the activation of chondrocytes, matrix degradation, and the role of inflammatory mediators. It also highlights the importance of biomechanical stress, aging, and the interaction between different tissues in the progression of OA. The authors emphasize the need for a systems approach to understand the complex interactions within the joint and to develop effective treatments.